This invention relates to puffer type interrupters, and more specifically relates to a novel arrangement to control the pressure created between a cylinder and piston which forces gas through the nozzle of the puffer interrupter during interruption so that the necessary operating force for operating the interrupter is reduced.
Puffer type interrupters are well known in the art wherein a pair of separable contacts are contained within a chamber which is filled with gas such as sulfur hexafluoride or another similar gas or gas mixture having good arc interruption properties. One of the contacts is fixed to a nozzle which is usually of insulation material and which is mounted on one of a piston or cylinder which are moved relative to one another when the contacts are operated in order to produce high-speed movement of fluid through the nozzle and between the separating cooperating contacts so that the arc drawn between the contacts will be extinguished. An operating mechanism is connected to the contacts in order to move the contacts and to cause relative movement between the piston and cylinder during the opening and closing operations.
In prior art puffer type interrupters, the operating mechanism is required to provide substantial operating force since the motion of the contacts to their open position is more and more strongly resisted as the pressure within the cylinder increases due to greater compression of the volume between the cylinder and the piston.